Threshold cap



FIG. 1 is an end view of our new design;

FIG. 2 is an end perspective of our new design;

FIG. 3 is an end view of our new design shown in a first position relative to environmental elements; and,

FIG. 4 is an end view of our new design shown in a second position relative to environmental elements.

The views not shown form no part of the claimed design. The dash-dot lines in FIGS. 1-4 represent unclaimed boundaries of the present design. The dash-dash lines in FIGS. 1-4 represent environmental elements only and form no part of the claimed design. 

CLAIM The ornamental design for a threshold cap, as shown and described. 